WO2016188981A1 - Plaque de flexographie pouvant être pourvue d'une image numérique, dotée d'une couche barrière intégrée - Google Patents

Plaque de flexographie pouvant être pourvue d'une image numérique, dotée d'une couche barrière intégrée Download PDF

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Publication number
WO2016188981A1
WO2016188981A1 PCT/EP2016/061640 EP2016061640W WO2016188981A1 WO 2016188981 A1 WO2016188981 A1 WO 2016188981A1 EP 2016061640 W EP2016061640 W EP 2016061640W WO 2016188981 A1 WO2016188981 A1 WO 2016188981A1
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WO
WIPO (PCT)
Prior art keywords
flexographic printing
layer
barrier layer
printing element
photopolymerizable
Prior art date
Application number
PCT/EP2016/061640
Other languages
German (de)
English (en)
Inventor
Matthias Beyer
Armin Becker
Original Assignee
Flint Group Germany Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Flint Group Germany Gmbh filed Critical Flint Group Germany Gmbh
Priority to MX2017015163A priority Critical patent/MX2017015163A/es
Priority to ES16724889T priority patent/ES2781325T3/es
Priority to CN201680030581.0A priority patent/CN107969149B/zh
Priority to EP16724889.7A priority patent/EP3304203B1/fr
Priority to BR112017025209-0A priority patent/BR112017025209B1/pt
Priority to EP19209908.3A priority patent/EP3633454A1/fr
Priority to US15/577,103 priority patent/US10518571B2/en
Priority to JP2017561684A priority patent/JP2018517179A/ja
Publication of WO2016188981A1 publication Critical patent/WO2016188981A1/fr

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/20—Exposure; Apparatus therefor
    • G03F7/2002—Exposure; Apparatus therefor with visible light or UV light, through an original having an opaque pattern on a transparent support, e.g. film printing, projection printing; by reflection of visible or UV light from an original such as a printed image
    • G03F7/2014—Contact or film exposure of light sensitive plates such as lithographic plates or circuit boards, e.g. in a vacuum frame
    • G03F7/2016—Contact mask being integral part of the photosensitive element and subject to destructive removal during post-exposure processing
    • G03F7/202—Masking pattern being obtained by thermal means, e.g. laser ablation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
    • B41N1/00—Printing plates or foils; Materials therefor
    • B41N1/12—Printing plates or foils; Materials therefor non-metallic other than stone, e.g. printing plates or foils comprising inorganic materials in an organic matrix
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C1/00—Forme preparation
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004—Photosensitive materials
    • G03F7/0047—Photosensitive materials characterised by additives for obtaining a metallic or ceramic pattern, e.g. by firing
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004—Photosensitive materials
    • G03F7/027—Non-macromolecular photopolymerisable compounds having carbon-to-carbon double bonds, e.g. ethylenic compounds
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004—Photosensitive materials
    • G03F7/09—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers
    • G03F7/092—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers characterised by backside coating or layers, by lubricating-slip layers or means, by oxygen barrier layers or by stripping-release layers or means
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004—Photosensitive materials
    • G03F7/09—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers
    • G03F7/11—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers having cover layers or intermediate layers, e.g. subbing layers
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/26—Processing photosensitive materials; Apparatus therefor
    • G03F7/36—Imagewise removal not covered by groups G03F7/30 - G03F7/34, e.g. using gas streams, using plasma

Definitions

  • the present invention relates to digitally imageable flexographic printing plates for the production of flexographic printing plates, which comprise a carrier film, an organic soluble, fotopolyme sierbare layer, an organic soluble barrier layer for oxygen, an organic soluble, laserablatierbare mask layer and a cover sheet.
  • Characteristics of the flexographic printing plates according to the invention are a good, coordinated adhesion between the individual layers and a simple and safe handling during processing to the cliché. Further, the flexographic printing plates of the present invention have a high resolution and excellent color transfer properties.
  • Digitally imageable flexographic printing plates are known in principle. They comprise at least one dimensionally stable carrier film, a photopolymerizable layer and a digitally imageable layer.
  • the digitally imageable layer can be, for example, a laser-ablatable layer, a record writable by an ink-jet printer, or a thermographic layer, with laser-ablatable layers being the most common.
  • Laser ablatable layers also called LAMS (laser ablatable mask layers)
  • LAMS laser ablatable mask layers
  • LAMS laser ablatable mask layers
  • Soot also causes the layer to be opaque.
  • a mask can be inscribed into the laser-ablatable layer by means of an IR laser, ie the layer is decomposed at the points where it is struck by the laser beam and the photopolymerizable layer arranged underneath is exposed.
  • the laser-ablatable mask layer can be applied directly to the photopolymerizable layer, or further layers can be present between the photopolymerizable layer and the laser-ablatable mask layer, for example a barrier layer. Examples of the imaging of flexographic printing elements with IR-ablative masks are disclosed, for example, in US 5,262,275 or EP-A 1 069 475.
  • flexographic printing plates starting from photopolymerizable, digitally imageable flexographic printing elements takes place as follows: After writing a mask into the digitally imageable layer, the flexographic printing element is exposed through the mask to UVA radiation. The photopolymerizable layer polymerizes in the areas no longer covered by the mask, while no polymerization takes place in the covered areas. After exposure, the remainders of the mask and the unpolymerized portions of the photopolymerizable layer are removed. This can be done using one or more solvents or thermally. When organic solvents are used, a drying step follows and usually the resulting flexographic printing plate is further treated, for example by exposure to UVA and / or UVC light. In digitally imageable flexographic printing elements, the main exposure by UVA radiation is usually in the presence of atmospheric oxygen.
  • the disturbing influence of oxygen during the exposure of flexographic printing elements should be switched off, so that the intended relief elements are completely polymerized to the surface, and thus finer details can be imaged on the plate. Furthermore, it would be desirable to be able to influence the surface properties of the flexographic printing plate in a targeted manner in order to improve the ink transfer and the color-change behavior. It has therefore been proposed to protect the photopolymerizable layer from oxygen during the main exposure. Thus, it is in principle possible to expose under protective gas (see, for example, US 8,241,835) or using a vacuum frame, but this approach is associated with additional equipment and is therefore usually avoided.
  • WO 2005/101 130 A1 discloses a multilayer mask film for the production of flexographic printing plates.
  • the mask film is imaged with a laser and then laminated onto the flexographic printing element with the lasered layer side.
  • the support layer of the masking film acts as a barrier to oxygen in the subsequent exposure to UVA radiation.
  • US 5,262,275 discloses flexographic printing elements comprising a support, a photopolymerizable layer, a barrier layer coated thereon, and a laser-ablatable mask layer disposed thereon.
  • the barrier layer is intended to prevent the migration of components, for example of monomers from the photopolymerizable layer, into the laser-ablatable layer and, on the other hand, to protect the photopolymerizable layer from atmospheric oxygen during the exposure of the flexographic printing element.
  • materials for the barrier layers are mentioned polyamides, polyvinyl alcohol, hydroxyalkyl cellulose, ethylene-vinyl acetate copolymers, amphoteric interpolymers and combinations thereof.
  • the thickness of the barrier layer is 0.25 ⁇ to 76 ⁇ , preferably 0.38 to 64 ⁇ .
  • Comparable constructed flexographic printing elements are described in WO 2012/1451 1 1 A1.
  • materials for the barrier layer polyamides, polyvinyl alcohol, hydroxyalkyl cellulose, polyvinyl pyrrolidone, ethylene-vinyl acetate copolymers, amphoteric interpolymers, cellulose acetate butyrate, alkyl cellulose, butyral, cyclic rubbers or combinations thereof are proposed.
  • the barrier layer should have a diffusion coefficient for O2 less than 6.9 * 10 "9 m 2 / s and an optical transparency of at least 50%, preferably at least 75%.
  • the thickness of the barrier layer is 1 to 100 ⁇ , preferably 1 to 20 ⁇ .
  • US Pat. No. 8,492,074 B2 describes digitally imageable flexographic printing elements with a barrier layer of at least two different resins.
  • the barrier layer is either laminated after imaging or may already be present in the flexographic printing plate as an integral part.
  • the resins of the barrier layer are preferably selected from the group of polyvinylpyrrolidone, shellac, polyvinyl butyral, polyvinylidene chloride or vinyl chloride copolymers.
  • EP 2284612 describes barrier layers of water-soluble polyamides, polyvinyl alcohol, polyacrylic acid, polyethylene oxide, cellulose and cellulose derivatives.
  • EP 1 156368 describes barrier layers of alkali-soluble cellulose derivatives with plasticizers for making the layer more flexible.
  • water-washable flexographic printing plates are only of limited use for high-quality flexographic printing because they swell in the polar dye solvents and do not allow a constant print quality.
  • WO 2015/040094 describes flexographic printing plates which have a water-soluble laser-ablatable mask layer and a water-soluble barrier layer on a photopolymerizable layer which is soluble in organic solvents.
  • As the material for the barrier layer partially hydrolyzed polyvinyl acetate copolymers are preferred.
  • these flexographic printing plates must be washed out in a two-step process, which in turn involves higher costs.
  • a general problem of multilayered flexographic printing plates is the required graded adhesion between the individual layers.
  • the cover film must be securely anchored to the laser-ablatable mask layer, because during the transport of the plate or when cutting the plate, the cover film must not come off the edge of the plate.
  • the cover foil Before the imaging by laser the cover foil has to be removed. The removal must be possible even with large formats without special effort.
  • the laser ablatable mask layer and the barrier layer must remain completely on the plate. These two layers must therefore adhere very well to each other and the composite of both layers must in turn adhere very well to the photopolymerizable layer.
  • the photopolymerizable layer must always remain adherent to the dimensionally stable carrier film.
  • the object of the invention is to formulate digitally imageable flexographic printing plates with integral barrier layer and laserablatierbarer mask layer, which can be processed with commercially available, based on organic solvents washing-out.
  • the flexographic printing plate should be constructed in such a way that it can be easily imaged with commercially available lasers and processed with all commercially available UVA imagesetters.
  • the handling of the flexographic printing plate should be simple, easy and secure.
  • a digitally imageable, photopolymerizable flexographic printing element for the production of flexographic printing plates, comprising at least one stacked one above the other in the stated order
  • Binder an ethylenically unsaturated monomer and a photoinitiator or a photoinitiator system
  • (E) a peelable coversheet, characterized in that the layers (B), (C) and (D) are soluble or dispersible in an organic solvent, and
  • the barrier layer (C) contains at least one oxygen-blocking binder and one oligomeric or polymeric basic adhesive component.
  • flexographic printing form or “cliché” are used for an already networked, print-ready printing form.
  • flexographic printing element or “flexographic printing plate” are commonly used for the photopolymerizable starting material used to make flexographic printing plates.
  • the flexographic printing plates according to the invention comprise at least the following superimposed layers: a dimensionally stable support (A), a relief-forming layer (B), a barrier layer (C), a laser-ablatable mask layer (D) and a cover film (E).
  • A dimensionally stable support
  • B relief-forming layer
  • C barrier layer
  • D laser-ablatable mask layer
  • cover film E
  • further layers eg further adhesive layers, may be present.
  • the core of the invention is the composition of the barrier layer (C), which contains at least one oxygen-blocking, organic solvent-soluble binder as the main component and an oligomeric or polymeric basic adhesive component as a minor constituent.
  • the composition of this barrier layer is crucial for the adhesion of the layer composite.
  • the flexographic printing plates of the invention can be handled safely and processed with commercially available lasers and exposure equipment.
  • Another characteristic of the invention is that the layers (B), (C) and (D) are soluble or dispersible in organic solvents.
  • the flexographic printing plates according to the invention can be processed with customary solvents for flexographic plates in customary washing-out devices, with customary processing times and up to the usual solids contents of the solvents.
  • solvents for flexo plates for example, Flexosol ® (Dupont) or nylosolv ® (Flint Group). These solvents contain as the main component a nonpolar hydrocarbon solvent and as a minor component a moderately polar alcohol.
  • the flexographic printing plates according to the invention exhibit the desired high resolution.
  • the barrier layer also contains a filler by means of which the surface topography of the flexographic printing plates can be adjusted in a targeted manner and the color transfer of the flexographic printing plates can be significantly improved.
  • the composition of the individual layers will be described in more detail below.
  • the flexographic printing element according to the invention comprises a dimensionally stable carrier in a manner known in principle.
  • dimensionally stable carrier films which usually have a thickness of 50 to 300 ⁇ .
  • the material of the carrier film may be, for example, steel or aluminum or plastics such as, for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate or polycarbonate.
  • PET films with a thickness of 100 to 200 ⁇ .
  • the dimensionally stable supports (A) can optionally be treated with conventional, adhesion-promoting layers.
  • the flexographic printing plate comprises at least one photopolymerizable, relief-forming layer (B).
  • the photopolymerizable relief-forming layer can be applied directly to the support.
  • other layers may also be present between the carrier and the relief-forming layer, for example adhesive layers or elastic or compressible lower layers.
  • the photopolymerizable, relief-forming layer (B) comprises at least one elastomeric binder, an ethylenically unsaturated compound, a photoinitiator or a photoinitiator system and optionally one or more further components, for example plasticizers, processing aids, dyes and UV absorbers.
  • Elastomeric binders for the production of flexographic printing elements are known to the person skilled in the art. Examples include styrene-diene block copolymers, natural rubber, polybutadiene, polyisoprene, styrene-butadiene rubber, nitrile-butadiene rubber, butyl rubber, styrene-isoprene rubber, styrene-butadiene-isoprene rubber, polynorbornene rubber or ethylene Propylene-diene rubber (EPDM). Preference is given to using hydrophobic binders. Such binders are soluble in organic solvents.
  • the elastomer is preferably a thermoplastic elastomeric block copolymer of alkenylaromatics and 1,3-dienes.
  • the block copolymers may be linear, branched or radial block copolymers. These are usually ABA-type triblock copolymers, but may also be AB-type diblock polymers, or those having multiple alternating elastomeric and thermoplastic blocks, eg, ABABA. It is also possible to use mixtures of two or more different block copolymers. Commercially available triblock copolymers often contain certain proportions of diblock copolymers.
  • the diene units can be 1, 2 or 1, 4 linked.
  • Both styrene-butadiene or styrene-isoprene type block copolymers and styrene-butadiene-isoprene type block copolymers can be used. They are available, for example under the name Kraton ® commercially. Furthermore possible to employ thermoplastic-elastomeric block copolymers having end blocks of styrene and a random styrene-butadiene middle block, which are available under the name Styroflex ®. The block copolymers may also be fully or partially hydrogenated, as in SEBS rubbers.
  • Preferred elastomeric binders are triblock copolymers of the ABA type or radial block copolymers of the type (AB) n, wherein A is styrene and B is diene, and random copolymers and random copolymers of styrene and a diene.
  • the total amount of elastomeric binders is in the case of the relief-forming layer (B) usually 40 to 90 wt .-% with respect to the sum of all components of the relief-forming layer, preferably 40 to 80 wt .-% and particularly preferably 45 to 75 wt .-%.
  • the photopolymerizable relief-forming layer (B) further comprises in a known manner at least one ethylenically unsaturated compound which is compatible with the binders. Suitable compounds have at least one ethylenically unsaturated double bond and are polymerizable. These are therefore referred to below as monomers. Esters or amides of acrylic acid or methacrylic acid with monofunctional or polyfunctional alcohols, amines, amino alcohols or hydroxy ethers and esters, esters of fumaric or maleic acid, vinyl ethers, vinyl esters or allyl compounds have proved to be particularly advantageous.
  • the amount of monomers in the photopolymerizable relief-forming layer (B) is generally not more than 20 wt .-% with respect to. the amount of all components of the photopolymerizable relief-forming layer (B), in general, is from 3 to 15 wt .-%.
  • the photopolymerizable relief-forming layer (B) further comprises in a known manner at least one photoinitiator or a photoinitiator system.
  • suitable initiators are benzoin or benzoin derivatives, such as methyl benzoin or benzoin ethers, benzil derivatives, such as benzil ketals, acylarylphosphine oxides, acrylarylphosphinic esters, ⁇ -hydroxyketones, polynuclear quinones or benzophenones.
  • the amount of photoinitiator in the relief-forming layer is generally up to 10 wt .-% with respect to the amount of all components of the relief-forming layer.
  • the photoinitiator (s) should be very soluble in the relief-forming layer and should not tend to crystallize.
  • the relief-forming layer (B) may contain plasticizer.
  • plasticizers are modified and unmodified natural oils and resins, such as high-boiling paraffinic, naphthenic or aromatic mineral oils, synthetic oligomers or resins such as oligostyrene, high-boiling esters, oligomeric styrene-butadiene copolymers, oligomeric methylstyrene copolymers, liquid oligobutadienes, liquid oligoisoprenes or liquid oligomeric acrylonitrile-butadiene copolymers or oligomeric ethylene-propylene-diene copolymers.
  • natural oils and resins such as high-boiling paraffinic, naphthenic or aromatic mineral oils, synthetic oligomers or resins such as oligostyrene, high-boiling esters, oligomeric styrene-butadiene copolymers, oligomeric methylstyrene copolymers, liquid oligobutadienes
  • polybutadiene oils in particular those having a molecular weight of 500 to 5000 g / mol, high-boiling aliphatic esters and mineral oils. It is also possible to use mixtures of different plasticizers.
  • the amount of optional plasticizer is determined by one skilled in the art according to the desired properties of the layer. It is generally 0 to 50 wt .-%, preferably 0 to 40 wt .-% of the sum of all components of the photopolymerizable relief-forming layer (B).
  • the relief-forming layer (B) may further contain other functional additives, for example, as described in US 8,808,968, small amounts of phosphites, phosphines, thioethers and amino-functional compounds.
  • the relief-forming layer (B) may contain surface-active substances such as hydrophobic waxes or siliconized or perfluorinated compounds, as described in US Pat. No. 8,114,566. These substances migrate from the relief layer to the surface during the drying of the flexographic printing plates, have a repellent effect on the printing ink and, in the printing process, cause less fine rasters to be polluted and the printing plates to be cleaned less frequently.
  • An essential feature of the relief-forming (B) layer is that it is soluble in the commonly available, commercially available flexo wash detergents.
  • Commercially available washout agents for flexographic printing plates for example, nylosolv ® Flint Group or Flexosol ® from Dupont. These washout agents consist of one or more nonpolar hydrocarbon solvents as the main constituent and a moderately polar alcohol, for example n-pentanol, cyclohexanol, ethylhexanol or heptyl alcohols, as a minor constituent.
  • the relief-forming layer (B) can be processed in these washout agents in usual times. Up to a solids content of at least 5% by weight, no contamination of the washout devices and no settling of solids in the washout solution are observed.
  • the thickness of the relief-forming layer (B) is generally 0.1 to 7 mm, preferably 0.5 to 4 mm and particularly preferably 0.7 to 2.5 mm.
  • the flexographic printing element according to the invention may also comprise a plurality of photopolymerizable, relief-forming layers which are soluble or dispersible in organic solvents. Flexographic printing elements having a multilayer structure of the photopolymerizable, relief-forming layer are likewise known to the person skilled in the art.
  • the barrier layer for oxygen (C) is also soluble in the conventional, commercially available flexo wash-off agents. par- dere results by the presence of the barrier layer no significant extension of the washout. The extension of the washout time in direct comparison to a flexographic printing plate without a barrier layer is a maximum of 10%. Up to a solids content of at least 5% by weight, no contamination of the washout devices and no settling of solids in the washout solution are observed.
  • the term "transparent to UVA light” does not exclude that certain proportions of the UVA light can be absorbed, but in any case it is ensured that the UVA exposure of the flexographic printing element allows polymerization of the relief-forming layer (B) is.
  • the barrier layer (C) has the essential task of preventing the subsequent diffusion of oxygen into the relief-forming layer (B) during the full-surface exposure of the flexographic printing element.
  • the oxygen permeability of the barrier layer is generally less than 1000, preferably less than 500 (cm 3 x 100 m) / (m 2 xdx bar).
  • the barrier layer (C) comprises at least one oxygen-barrier binder and an oligomeric or polymeric basic adhesive component. Another requirement for the binder of the barrier layer results from the processing of the flexographic printing plate. During the processing of the flexographic printing plate to the flexographic printing plate, it is first imaged by means of an IR laser. This is usually done with laser equipment comprising a rotating drum for receiving the flexographic printing plate. During assembly, the flexographic printing plate is bent and the surface is stretched. The subsequent surface exposure with UVA light is generally carried out using flatbed plates, so that the flexographic printing element is bent straight again after imaging.
  • the barrier layer (C) may not tear during mounting on the drum and after disassembly and straight bending must not form any wrinkles, waves or other disturbing structures.
  • the binders of the barrier layer (C) are therefore soft-elastic binders.
  • any soft elastic binder can be used for the barrier layer (C) with which the required maximum oxygen permeability is reached or fallen below, provided that the other boundary conditions such as transparency for UVA light and solubility in the commercially available flexo wash detergents are also met.
  • Suitable soft elastic polymers which are soluble in organic solvents and have a sufficient barrier to oxygen are, for example, partially hydrolyzed polyvinyl acetates having a degree of saponification between 30 and at most 80 mol%, ethylene-vinyl acetate copolymers and ethylene-vinyl alcohol copolymers and ethylene-vinyl acetate vinyl alcohol copolymers.
  • cyclic acetals of polyvinyl alcohol such as polyvinyl butyral, polyvinyl ethyl pyrrole, polyvinyl formal, polyvinyl propyral, and copolymers containing two or more different vinyl acetal units selected from vinyl formal, vinyl ethyral, vinyl propyral, and vinyl butyral units.
  • polyvinyl alcohol such as polyvinyl butyral, polyvinyl ethyl pyrrole, polyvinyl formal, polyvinyl propyral, and copolymers containing two or more different vinyl acetal units selected from vinyl formal, vinyl ethyral, vinyl propyral, and vinyl butyral units.
  • Butvar ® and Mowital ® commercially available under the trade names Butvar ® and Mowital ® .
  • the polyvinyl acetals are always copolymers with vinyl alcohol units, since the reaction of polyvinyl alcohol into the full acetal is not complete for statistical and steric reasons
  • the residual OH content of said polyvinyl acetals is between 10 and 30% by weight.
  • the adhesion of the barrier layer (C) to the slightly tacky, relief-forming layer (B) is sufficiently high. Due to the non-polar nature of the binder of the barrier layer (C) and the resulting low interaction forces, however, the connection to the laser-ablatable mask layer (D) is problematic. Surprisingly, it has been found that the binding of the barrier layer (C) to the mask layer (D) is insufficient even if identical polymeric binders are used in both layers. However, a good connection of the individual layers to each other is of crucial importance for the handling of the flexographic printing plate in the processing to the cliché.
  • the laser-ablatable mask layer (D) when removing the cover film, the laser-ablatable mask layer (D) must remain completely on the barrier layer (C) and this in turn completely on the relief-forming layer (B). Does it come with Removing the cover film for partial detachment of individual layer parts, the entire flexographic printing plate is thus unusable.
  • the adhesion of the barrier layer to the laserablatierbaren mask layer (D) can be significantly improved by the addition of an oligomeric or polymeric basic adhesive component to the barrier layer (C), and the flexographic printing plates of the invention can then be processed easily and safely.
  • Suitable adhesion components are, for example, copolymers or cooligomers with basic carboxylate or sulfonate functions, such as, for example, neutralized or partially neutralized styrene-acrylic acid copolymers, styrene-acrylate-acrylic acid copolymers or neutralized or partially neutralized ethylene-acrylic acid copolymers, ethylene-methacrylic acid copolymers and ethylene-acrylate-acrylic acid or methacrylic acid copolymers.
  • Very suitable are oligomers and polymers with basic amino functions such as polyvinylamine or polyethyleneimine.
  • the amino group-containing oligomers or polymers are preferably used in unneutralized form. For adhesion, the presence of a basic group seems essential.
  • the number average molecular weight of the basic adhesive component should be at least 500 g / mol. Adhesion improvement can be achieved at lower molecular weights, but this is not permanent, presumably because the small molecules can migrate into the other layers. Preference is therefore given to using adhesive components having a number-average molecular weight of at least 1000 g / mol and very particularly preferably having a number-average molecular weight of at least 10,000 g / mol.
  • the oligomeric (1000 g / mol to 10000 g / mol) or polymeric adhesive component (> 10000 g / mol) may be linear or branched or else hyperbranched. In particular, the polyethyleneimines may have different degrees of branching, which may be expressed by the percentage of primary to secondary to tertiary amino groups.
  • the proportion of the basic adhesive component in the barrier layer is from 1 to 30 wt .-%, preferably from 3 to 15 wt .-%.
  • the barrier layer (C) additionally contains a filler.
  • Suitable fillers are inorganic fillers such as silicates, quartz flours, glass particles, silicon oxides or aluminum or titanium oxides but also natural minerals such as hydroxyapatite, talc, calcium sulfate or calcium carbonate or pigments such as iron or chromium oxides in question.
  • the fillers may be surface-treated or surface-functionalized to ensure uniform dispersion of the filler particles in the barrier layer (C).
  • organic materials such as polyethylene, polycarbonates and poly (meth) acrylates may also be used.
  • the filler particles may be crosslinked or uncrosslinked and may also be functionalized with organic functional groups.
  • the shape of the fillers is arbitrary. Round particles or crystalline particles of any shape can be used. However, the shape of the particles has a decisive influence on the topography of the respective surface. Thus, customized surfaces can be formulated for different color systems and various printing applications, for example for the printing of flexible packaging, label printing or printing on paper, cardboard or corrugated board.
  • the process of taking the topography of the barrier layer (C) onto the relief-forming layer (B) may be different.
  • the filler particles will react with the surface-UVA exposure with the monomers of the relief-forming layer.
  • the filler is transferred to the relief-forming layer.
  • this process can be proven by microscopic images.
  • the filler particles then stand out of the surface of the flexoclassics. The topography is transmitted.
  • Unfunctionalized fillers are not incorporated into the relief-forming layer, but only mechanically delaminate into the soft relief-forming layer. The filler particles are removed when the relief is washed out. As a result, corresponding pits or holes are later observed on the printing plate.
  • the topography of the barrier layer (C) is only molded. Which process to favor for optimal printing results can not be generally predicted. Different topographies can have completely different effects for different ink systems and printing applications. In principle, however, a flexographic printing plate according to the invention should either form or transfer the topography. Partial transfer and partial molding is not helpful for consistent surface quality.
  • the transfer or impression of the surface topography of the barrier layer (C) on the relief-forming layer (B) only 1: 1, if the barrier layer has the required low oxygen permeability. If other polymers with higher oxygen permeability are used as binders for the barrier layer, then the oxygen that diffuses after UVA exposure prevents cross-linking of the surface of the relief-forming layer. The uppermost layer is then removed during washing so that the topography is not transferred 1: 1 or molded.
  • the transfer or impression of the topography must be made evenly on all relief elements, solid surfaces and fine grid points. This is possible in particular if the binders according to the invention with low oxygen permeability are used as binders. Especially good is the Transfer or impression of the topography if the polyvinyl acetals according to the invention are used as binders and inorganic silicates or silica are used as fillers.
  • the average particle size of the fillers is in a range of 2 to 15 ⁇ , preferably from 3 to 8 ⁇ .
  • the proportion of the inorganic fillers in the barrier layer is in a range of 5 to 30 wt .-%. At higher levels, the transparency of the barrier layer is reduced too much. For smaller proportions no microscopically uniform roughness is achieved. If organic fillers are used, the refractive index between the filler and the matrix polymer can be adjusted, so that in this case higher filler proportions (up to 50% by weight) can be realized.
  • barrier layer (C) normally makes it stiffer and tack-free, resulting in reduced adhesion, thereby increasing the above-described adhesion problems between the barrier layer (C) and the mask layer (D). Therefore, in this embodiment, it is of particular importance to use an oligomeric or polymeric basic adhesive component in the barrier layer (C).
  • the oxygen-barrier barrier layer contains (C)
  • the layer thickness of the barrier layer (C) is usually 0.3 ⁇ to 5 ⁇ . With layer thicknesses below 0.3 ⁇ m, it is difficult to achieve a homogeneous, uniform application and a sufficiently uniform barrier effect with respect to oxygen. At layer thicknesses above 5 ⁇ the imaging accuracy can be reduced by increasing scattering effects of UVA light and the extensibility of the layer is impaired.
  • the layer thickness is therefore 0.5 ⁇ to 3 ⁇ , more preferably 1 ⁇ to 2 ⁇ .
  • the layer thicknesses can be measured, for example by microscopic Shooting a section, or they can alternatively be calculated from the order weight and the density of the applied material.
  • a laser-ablatable mask layer (D) which is soluble or dispersible in organic solvents is applied to the barrier layer (C).
  • the information to be printed is inscribed in the laser-ablatable mask layer (D) by means of a suitable laser.
  • the mask layer (D) comprises at least one elastomeric, organic solvent-soluble binder and UV-VIS light absorbing components.
  • the presence of the mask layer does not substantially prolong the washout of the flexographic printing plates according to the invention in commercially available washout agents.
  • the mechanical requirements for the binders of the mask layer also meet the mechanical requirements for the binders of the barrier layer.
  • the mask layer must not break during bending / stretching and should not wrinkle or curl when straightened. Therefore, the binders are generally soft elastic.
  • the binder of the barrier layer may be identical to the binder of the mask layer, but it may be different.
  • soft elastic binder for the mask layer for example, ethylene vinyl acetates, soft elastic polyamides, soft elastic polyurethanes, nitrocellulose, polyvinyl acetals such as poly (vinybutyral- vinyl alcohol) copolymers (Butvar ®, Mowital ®), or poly (vinyl butyral-vinylethyral- vinyl alcohol) copolymers ( pioloform ®).
  • ethylene vinyl acetates for example, ethylene vinyl acetates, soft elastic polyamides, soft elastic polyurethanes, nitrocellulose, polyvinyl acetals such as poly (vinybutyral- vinyl alcohol) copolymers (Butvar ®, Mowital ®), or poly (vinyl butyral-vinylethyral- vinyl alcohol) copolymers ( pioloform ®).
  • other soft elastic materials can be used as a binder, such as partially hydrolyzed polyvinyl acetates.
  • the laser-ablatable mask layer (D) contains UV / VIS light-absorbing materials, the layer thickness and / or the amount of light-absorbing materials generally being dimensioned such that the optical density of the layer for UVA radiation is 1 to 5.
  • the UVA radiation range comprises light of the wavelength of 300 to 400 nm.
  • the optical density is the logarithmic measure of the opacity of the layer in this wavelength range. In the measurement of the optical density, therefore, no individual value of the opacity at a specific wavelength is determined, but an average of the opacities in a defined wavelength range.
  • the measurement of the optical density by means of commercially available densitometers (eg from x-rite), wherein the wavelength range is selected before the measurement.
  • all cited measured values of the optical density relate to the UVA range, ie the range from 300 to 400 nm.
  • Preferred optical densities of the mask layer (D) are in the range from 2 to 5.
  • the high optical density ensures that the areas of the relief-forming layer (B) covered by the mask do not polymerize in the course of the full-surface exposure to UVA light.
  • Finely divided carbon black, graphite or carbon black nanoparticles or carbon nanotubes are particularly suitable as the light-absorbing material. These absorb very well in the near IR range and thus ensure fast imaging in the imaging by means of IR lasers, such as, for example, IR laser diodes (830 nm) or Nd-YAG lasers (1064 nm).
  • IR lasers such as, for example, IR laser diodes (830 nm) or Nd-YAG lasers (1064 nm).
  • the laser ablatable mask layer (D) but also other UV or IR absorbers based on pigments or soluble dyes.
  • dyes for example, phthalocyanines and substituted phthalocyanine derivatives, cyanine and merocyanine dyes or polymethine dyes or azo dyes can be used.
  • the disadvantage of the molecular soluble dyes is that they can diffuse from the laser-ablatable masking layer to other layers of the flexographic printing element, thereby reducing the optical density of the masking layer and increasing that of the other layers, with the result that the processing times of the flexographic printing plate exceed change the storage time. Furthermore, the quality of the clichés produced is reduced. For this reason, UV and IR absorbers based on pigments such as carbon black, graphite and carbon nanoparticles or carbon nanotubes are preferred.
  • the amount of the light-absorbing materials is usually from 10% by weight to 60% by weight with respect to the amount of all the components of the laser-ablatable mask layer.
  • the laser-ablatable mask layer (D) may optionally also contain plasticizers, stabilizers or other auxiliaries, for example emulsifiers, leveling agents or UV absorbers.
  • plasticizers for example emulsifiers, leveling agents or UV absorbers.
  • these materials must have such a high molecular weight that diffusion into other layers of the flexographic printing element is prevented due to molecular size, or the diffused materials in the other layers have no influence and function and thus do not interfere with the production of the flexographic printing plate.
  • the layer thickness of the laserablatierbaren mask layer (D) is generally preferably 0.3 ⁇ to 5 ⁇ . At layer thicknesses below 0.3 ⁇ it is difficult to achieve a sufficient optical density. With layer thicknesses of more than 5 ⁇ the laser sensitivity of the element is too low, so that long laser times are necessary for imaging.
  • the laser sensitivity of the mask layer (measured as the energy necessary to ablate 1 cm 2 layer) should be between 0.5 and 4 mJ / cm 2 . Preferably, the layer thickness is 1 ⁇ to 3 ⁇ .
  • the flexographic printing plates according to the invention contain as the uppermost layer a peelable cover film (E), which inter alia serves to protect the flexographic printing plate.
  • the cover sheet is peeled off before imaging the flexographic printing plate by means of the IR laser.
  • Suitable peelable cover films (E) are in particular PET films with moderate or low roughness.
  • Typical average single sowing depths (Rz) should be between 0.2 and 2.0 ⁇ m.
  • the Mittelrau values (Ra) should be between 0.02 and 0.5 ⁇ .
  • the roughness of the cover film is for the removal of the cover film from the composite of carrier film, relief-forming layer, barrier layer and mask layer important. The rougher the cover film, the greater the contact area between the cover film and the mask layer, and the greater the forces must be expended when the cover film is removed. A smooth film is therefore preferable for safe handling.
  • a smooth cover film has the further advantage that the application amount of the laser-ablatable mask layer can be reduced, which increases the laser sensitivity. This is not possible with a rough cover film since all the valleys of the cover film must be completely filled and all tips must be covered so that a high optical density is achieved over the entire surface and no holes occur.
  • a Mylar® A PET film can be used.
  • the production of the flexographic printing plates according to the invention is carried out in a manner known in principle by melting the components of the photopolymerizable layer in an extruder, mixing and discharging the melt of the photopolymerizable material through a slot die into the nip of a calender.
  • a prefabricated cover element runs over the one calender roll-optionally with further layers, such as an adhesive layer-coated carrier foil, and over the other calender roll.
  • the layer composite of dimensionally stable carrier film (A), photopolymerizable layer (B) and cover film (E) with the layers (D) and (C) is joined together by calendering.
  • the cover element is the cover film (E), which is precoated with the laser-ablatable mask layer (D) and the barrier layer (C).
  • the laserablatierbare mask layer (D) is applied to the cover sheet (E). This can be done from solution, from the melt or by spraying. Subsequently, the laserablatierbare mask layer (D) with the barrier layer (C) is covered. In order to avoid the dissolution of the first, already applied mask layer (D) during the overlaying with the barrier layer (C), it may be necessary to vary the solvent composition of the casting solutions. Before application of the next layer, it may be necessary to crosslink the surface to be coated by means of an electron beam in order to achieve a better overcoatability. A corona pretreatment of the first applied mask layer can also be helpful in order to achieve better bonding of the layers to one another. By way of limitation, it must be said that the effects of corona pretreatment often decrease with the storage time of the printing plate and no permanently good adhesion is achieved.
  • the individual layers can also be coated separately on different films and then laminated together.
  • the mask layer (D) and the barrier layer (C) can also be coated separately on a respective film.
  • the mask layer (D) is in this case applied to the subsequent cover film (E), while the barrier layer (C) is applied to a temporary auxiliary film. After coating, both films are laminated together with the layer sides and the temporary auxiliary film is peeled off.
  • Casting techniques for applying layers are known in the art.
  • the layer thickness of the layers to be applied can be reduced in a manner known in principle by dilution of the casting solution or change in the coating parameters, such as knife gap or coating speed.
  • the coated cover element is rolled up and retracted in the subsequent extrusion over one of the calender rolls and thus adherent bonded to the photopolymerizable, relief-forming layer (B).
  • parts of the cover element can also be laminated in several steps. For example, a cover element from a barrier layer (C) on a temporary auxiliary film on the calender rolls and retracted with the photopolymerizable layer (B) are connected. The auxiliary film is then peeled off. In a second laminating step, the laserablatierbare mask layer (D) is then laminated with the actual cover sheet.
  • the adhesion between barrier and laser ablatable mask layer builds up in the following days.
  • the adhesion of the printing plates according to the invention is constant only after a storage time of 2 weeks and adhesion measurements should only be carried out after this time. Processing of the flexographic printing elements according to the invention into flexographic printing plates
  • the production of flexographic printing plates from the flexographic printing elements according to the invention comprises the method steps (i) to (vi): (i) peeling off the cover film (E),
  • the invention also provides a process for the production of flexographic printing plates from the flexographic printing elements according to the invention, comprising the process steps (i) to (vi).
  • the invention also relates to the flexographic printing plates produced in this way.
  • step (i) the cover film (E) is removed from the flexographic printing element.
  • the laser-ablatable mask layer (D) and the barrier layer (C) must remain completely on the relief-forming layer (B). This is easily possible with the flexographic printing elements according to the invention.
  • step (ii) a mask is inscribed in the laser ablatable mask layer (D) using an IR laser.
  • Laser apparatus for writing masks are known in the art and are commercially available. In principle, all commercially available lasers (mainly external drum lasers) can be used.
  • the flexographic printing elements are stretched during assembly on the laser drum.
  • the barrier layer (C) and the laser-ablatable layer (D) must not tear, which is easily possible with the flexographic printing elements according to the invention.
  • the imaged flexographic printing element is exposed with UVA radiation through the mask formed and through the barrier layer (C).
  • the photopolymerizable layer polymerizes in the areas no longer covered by the mask, while no polymerization takes place in the covered areas.
  • the photopolymerizable layer is protected from the influence of post-diffusive oxygen during exposure through the barrier layer (C).
  • the exposure can therefore be carried out using commercially available UVA tube exposers or UV LED strips. Expensive exposure to exclusion of air or the elaborate lamination of a film or the lamination of a film blocking against oxygen are not necessary when using the flexographic printing elements according to the invention.
  • the residues of the laser-ablatable mask layer (D), and the barrier layer (C) and the unpolymerized portions of the relief-forming layer (B) are removed using commercially available flexo wash detergents in conventional processing times.
  • This can be done using conventional washout equipment, especially using flatbed washout equipment.
  • a washout agent is used which contains at least one organic solvent.
  • Commercially available flexo wash detergents are described, for example, in EP 332,070. In general, these contain aliphatic, cycloaliphatic or aromatic hydrocarbons and one or more alcohols. Most of the washing agents used in the market contain non-polar hydrocarbons as the main component and medium polar alcohols in an amount of 10 to 30% by weight.
  • washout agents examples include blends containing about 40% by weight high boiling point hydrocarbon solvents, about 40% Wt .-% decalin and about 20 wt .-% n-pentanol, mixtures containing about 50% high-boiling hydrocarbon solvents, about 20 wt .-% diisopropylbenzene and about 30 wt .-% cyclohexanol, mixtures containing about 56 wt % Of decalin, about 27% by weight of aliphatic hydrocarbon solvent, about 12% by weight of benzyl alcohol and about 2% by weight of ethylhexanol, and also mixtures containing about 70% by weight of aromatic hydrocarbons and about 30% by weight Wt .-% heptyl alcohols.
  • the flexographic printing elements according to the invention can also be thermally developed.
  • the flexographic printing elements are mounted on a drum and heated from the surface to melting. Subsequently, a fabric tape is pressed onto the flexographic printing elements and the unexposed areas of the relief-forming layer, the barrier layer and the remnants of the laser-ablatable mask layer are peeled off. This process is repeated several times until the desired relief depth is reached.
  • the flexographic printing plate obtained is optionally dried in a manner known in principle and post-exposed in step (vi) in a manner known in principle to UVA and / or UVC light.
  • the method may optionally include further method steps.
  • a pre-exposure can be carried out before or after the writing of the mask by means of an IR laser.
  • the flexographic printing elements according to the invention are exposed through the carrier film, whereby a uniform relief base is produced and the height of the desired relief can be adjusted.
  • Makromelt ® 6900 a soft-elastic polyamide from Henkel.
  • Mowital ® B16H a polyvinyl butyral having a residual OH content of 19.5%, Kuraray.
  • Pioloform ® BL16 a poly (vinyl butyral-vinylethyral) copolymer having a residual OH content of 16% of the company Kuraray.
  • Loxanol MI ® 6735 a polyethyleneimine having a molecular weight of 25,000 g / mol from BASF.
  • Lupasol ® P a polyethyleneimine having a molecular weight of 750,000 g / mol from BASF.
  • Syloid ® ED 3 an amorphous silica having an average particle size of 5.8 ⁇ from Grace.
  • the invention will be described in more detail in the following examples. The tests were carried out on an industrial scale, which means that large-format flexographic printing plates in 1270 mm x 2032 mm format were produced. As a starting material a nyloflex ® NEF 1 14 D flexographic printing plate from Flint Group was used. All% figures are to be understood as proportional weight percentages.
  • the components of the relief-forming layer of the flexographic printing plate nyloflex ® NEF were mixed in a twin-screw extruder of the type ZSK and melted. The melt was discharged at a temperature of 130 ° C through a slot die and retracted into a calender. A PET cover film previously coated with the laser-ablatable mask layer and the barrier layer was retracted over the upper calender roll. About the lower calender roll, a PET carrier film was retracted. The composite was pulled off via a vacuum suction belt, cooled and cut to the desired 1270 mm x 2032 mm plate format. The flexographic printing plate had one Total thickness of 1, 27 mm. After a storage period of 2 weeks, the flexographic printing plates were measured and processed into flexographic printing plates.
  • a 0.1 mm thick Mylar® A PET film was used as the cover film.
  • the mask layer contained 65% Makromelt® 6900 and 35% Special Black 4.
  • the Makromelt® 6900 was dissolved in a solution consisting of equal parts of toluene and n-propanol. Subsequently, the special black 4 was added in portions and the solution was run for 5 hours on a ball mill. The solids content of the dispersion was 12%. The dispersion was then coated on the Mylar® A film by means of a doctor roller and dried at 75.degree.
  • the dry coating weight of the layer was 2.9 g / m 2 and the optical density was in the range of 3.7 to 4.0 over the entire coating width.
  • the cover sheet coated with the mask layer was then overcoated with the barrier layer.
  • the composition of the respective barrier layers is contained in the following table.
  • the binder was mixed in a solvent mixture consisting of 20% water and 80% isopropanol in room temperature. temperature dissolved. Subsequently, the adhesive component and optionally the filler were added and the solution or the dispersion was stirred for 30 minutes. The solid content of the coating solution was 12%. The coating solution was then applied to the mask layer via a doctor roll and dried at 65 ° C. The dry coat weight of the layer was 2.8 g / m 2 . The cover films thus coated twice were then introduced into the calender as described above and thus adhesively bonded to the relief-forming layer of the flexographic printing plate. Processing of the flexographic printing plates according to the invention into flexographic printing plates and printing
  • the flexographic printing plates were processed into clichés and evaluated.
  • the flexographic printing plates were first back about 30 seconds pre-exposed (nyloflex ® FV imagesetter, Flint Group).
  • the cover sheet was peeled off.
  • the peeling off of the coversheet was statistically evaluated.
  • the cover sheet of each 10 large-format plates were manually peeled off and the printing plates were examined for detachment at the edges and corners. The number of faultless plates was noted.
  • adhesion of the cover sheet and the adhesion of the laser-ablatable mask layer to the underlying barrier layer were determined. Adhesion measurements were made on 4cm wide strips on a Zwick tensile-strain tester.
  • the flexographic printing plates were then mounted on the drum of an IR laser ( CDI® Spark 4835 from Esko) and imaged with a suitable motif at a resolution of 2540 dpi.
  • the test motif contained a raster wedge with graduated tonal values (1% to 5% grids spaced 0.2% apart) at a resolution of 146 Ipi.
  • the thus prepared plate was subsequently for 14 minutes by UVA radiation exposed (FV nyloflex ® imagesetters, Flint Group) and then developed.
  • the solvent-based development of the imagewise exposed flexographic printing plates was carried out at the respectively indicated washout speed and with the brush position recommended for the respective product type with the aid of a nyloflex® F V-washer from Flint Group.
  • nylosolv® A from Flint Group was used, a commercial flexo-washout agent consisting of approx. 70% hydrocarbon solvent and approx. 30% alcohol.
  • the still solvent-based clichés were dried for 120 minutes at 60-65 ° C according to the product-specific recommendations and then post-exposed in the post-exposure unit of a nyloflex® F V exposure with UVA and UVC light.
  • the flexoclips were evaluated microscopically and the smallest halftone tone value, which could be perfectly imaged on the flexoclassical, was determined. Furthermore, the relief depth was determined. Subsequently, the Flexoklischees were printed with the following printing parameters.
  • Adhesive tape Lohmann 5.3
  • the optical density of a printed solid surface was determined.
  • FIG. 1 shows an electron micrograph of halftone dots of a flexoclassic according to V5.
  • the halftone dots correspond to a tone value of 2% at 146 lpi (lines per inch, lines per inch).
  • FIG. 2 shows an electron micrograph of halftone dots of a flexoclassic according to V5.
  • the grid points shown correspond to a tone value of 30% at 146 lpi (lines per inch, lines per inch).
  • FIG. 3 shows an electron micrograph of a full surface of a flexoclass according to V5.

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Abstract

L'invention concerne un élément de flexographie photopolymérisable, pouvant être pourvu d'une image numérique pour la fabrication de formes imprimantes flexographiques, comprenant dans l'ordre indiqué, disposés les uns au dessus des autres, au moins (A) un support stable en dimensions, (B) au moins une couche photopolymérisable formant un relief, ayant une épaisseur de couche de 300 à 6000 µm, comprenant au moins un liant élastomère, un monomère éthyléniquement insaturé ainsi qu'un photoinitiateur ou un système photoinitiateur, (C) une couche barrière bloquant l'oxygène, transparente pour la lumière UVA, ayant une épaisseur de couche de 0,3 à 5 µm, (D) une couche de masque éliminable au laser ayant une épaisseur de couche de 0,3 à 5 µm, comprenant au moins un liant élastomère et un matériau absorbant la lumière UVA/IS, ainsi que (E) un film de recouvrement pelliculable, les couches (B), (C) et (D) étant solubles ou dispersibles dans un solvant organique, et la couche barrière (C) contenant au moins un liant bloquant l'oxygène et un composant adhésif oligomère ou polymère basique. D'autres aspects de l'invention concernent un procédé de fabrication d'une forme imprimante flexographique et une forme imprimante flexographique pouvant être obtenue par le procédé.
PCT/EP2016/061640 2015-05-28 2016-05-24 Plaque de flexographie pouvant être pourvue d'une image numérique, dotée d'une couche barrière intégrée WO2016188981A1 (fr)

Priority Applications (8)

Application Number Priority Date Filing Date Title
MX2017015163A MX2017015163A (es) 2015-05-28 2016-05-24 Placa de impresion flexografica, con formacion de imagen digital, con capa de barrera integrada.
ES16724889T ES2781325T3 (es) 2015-05-28 2016-05-24 Placa de impresión flexográfica capaz de ser ilustrada digitalmente con capa de barrera integral
CN201680030581.0A CN107969149B (zh) 2015-05-28 2016-05-24 具有集成阻挡层的可数字成像柔版印版
EP16724889.7A EP3304203B1 (fr) 2015-05-28 2016-05-24 Plaque d'impression flexographique imageable de manière numérique pourvu d'une couche barrière intégrale
BR112017025209-0A BR112017025209B1 (pt) 2015-05-28 2016-05-24 Elemento de impressão flexográfica fotopolimerizável digitalmente convertível em imagem, e, método para produzir um elemento de impressão flexográfica fotopolimerizável digitalmente convertível em imagem
EP19209908.3A EP3633454A1 (fr) 2015-05-28 2016-05-24 Procédé de fabrication d'une plaque flexographique à partir d'un élément flexographique photopolymérisable réutilisable numériquement pourvu d'une couche de barrière intégrale
US15/577,103 US10518571B2 (en) 2015-05-28 2016-05-24 Digitally imageable flexo-printing plate with integrated barrier layer
JP2017561684A JP2018517179A (ja) 2015-05-28 2016-05-24 一体化したバリヤー層を有するデジタルイメージング可能なフレキソ印刷プレート

Applications Claiming Priority (2)

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EP15169554.1 2015-05-28
EP15169554 2015-05-28

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WO2016188981A1 true WO2016188981A1 (fr) 2016-12-01

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US (1) US10518571B2 (fr)
EP (2) EP3304203B1 (fr)
JP (2) JP2018517179A (fr)
CN (1) CN107969149B (fr)
BR (1) BR112017025209B1 (fr)
ES (1) ES2781325T3 (fr)
MX (1) MX2017015163A (fr)
WO (1) WO2016188981A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018091953A (ja) * 2016-12-01 2018-06-14 旭化成株式会社 フレキソ印刷原版
WO2019072701A1 (fr) * 2017-10-10 2019-04-18 Flint Group Germany Gmbh Précurseur en relief avec faible courbure transversale et plissage
US10843453B2 (en) 2016-10-10 2020-11-24 Akk Gmbh Composite panel with barrier layer and method for manufacturing a letterpress plate
EP3832389A1 (fr) 2019-12-06 2021-06-09 Folex AG Plaques d'impression flexographique à haute résolution et moyen de fabrication desdites plaques comprenant des couches barrière et d'adhésion améliorées
JP2021514482A (ja) * 2018-02-16 2021-06-10 ミラクロン コーポレーションＭｉｒａｃｌｏｎ Ｃｏｒｐｏｒａｔｉｏｎ マスク要素前駆体およびレリーフ像形成システム

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CN114683675B (zh) 2020-12-28 2023-11-14 乐凯华光印刷科技有限公司 一种表面自带纹理的平顶网点的柔性树脂版及其制版方法
CN114474959A (zh) * 2022-01-29 2022-05-13 乐凯华光印刷科技有限公司 一种阻氧层及包含其的凸起部分表面砂目化的自平顶网点数字化柔性树脂版
US20230350298A1 (en) * 2022-04-27 2023-11-02 Miraclon Corporation Flexographic printing mask with laser thermal imaging film

Citations (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0332070A2 (fr) 1988-03-10 1989-09-13 BASF Aktiengesellschaft Procédé pour le développement des plaques d'impression flexographiques exposées selon l'image
US5262275A (en) 1992-08-07 1993-11-16 E. I. Du Pont De Nemours And Company Flexographic printing element having an IR ablatable layer and process for making a flexographic printing plate
EP1069475A1 (fr) 1999-07-13 2001-01-17 BASF Drucksysteme GmbH Elément pour l'impression flexographique présentant une couche détachable par infrarouge et hautement sensible
EP1156368A2 (fr) 2000-05-17 2001-11-21 Tokyo Ohka Kogyo Co., Ltd. Matériau photosensible multicouche pour plaque d'impression flexographique
US20040038147A1 (en) * 2002-08-20 2004-02-26 Ray Kevin B. Flexographic element having an integral thermally bleachable mask layer
WO2005101130A1 (fr) 2004-04-10 2005-10-27 Eastman Kodak Company Procede de fabrication d'un hologramme
EP2128702A1 (fr) 2008-05-27 2009-12-02 Esko-Graphics Imaging GmbH Durcissement de plaques d'impressions photo-durcissables permettant d'obtenir des sommets plats ou arrondis
EP2284612A1 (fr) 2008-05-23 2011-02-16 Toyo Boseki Kabushiki Kaisha Cliché matrice pour impression flexographique
CN102103322A (zh) * 2009-12-17 2011-06-22 乐凯集团第二胶片厂 一种计算机直接制版的柔性版及其制备方法
US8114566B2 (en) 2006-04-07 2012-02-14 Asahi Kasei Chemicals Corporation Photosensitive resin composition for flexographic printing
US20120115083A1 (en) * 2010-11-04 2012-05-10 Vest Ryan W Biodegradable Film for Flexographic Printing Plate Manufacture and Method of Using the Same
US20120164584A1 (en) 2009-10-01 2012-06-28 Recchia David A Method of Improving Print Performance in Flexographic Printing Plates
US8241835B2 (en) 2008-01-30 2012-08-14 E I Du Pont De Nemours And Company Device and method for preparing relief printing form
WO2012145111A1 (fr) 2011-04-21 2012-10-26 Macdermid Printing Solutions, Llc Stratifié de résine photosensible et son traitement thermique
EP2596404A1 (fr) 2010-07-19 2013-05-29 Flint Group Germany GmbH Procédé comprenant une irradiation à del uv pour fabriquer des moules de flexographie
US8492074B2 (en) 2011-01-05 2013-07-23 Laurie A. Bryant Method of improving print performance in flexographic printing plates
US8808968B2 (en) 2012-08-22 2014-08-19 Jonghan Choi Method of improving surface cure in digital flexographic printing plates
WO2015040094A2 (fr) 2013-09-18 2015-03-26 Flint Group Germany Gmbh Élément flexographique pour imageage direct et procédé de fabrication de clichés

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5719009A (en) * 1992-08-07 1998-02-17 E. I. Du Pont De Nemours And Company Laser ablatable photosensitive elements utilized to make flexographic printing plates
DE19639897A1 (de) * 1996-09-27 1998-04-02 Sun Chemical Corp Wasserlösliche und sauerstoffsperrende Polymerschichten und deren Verwendung für lichtempfindliche Materialien
AU2002333253B2 (en) * 2001-08-03 2007-03-01 Xsys Print Solutions Deutschland Gmbh Photosensitive, flexo printing element and method for the production of newspaper flexo printing plates
US20040234886A1 (en) 2003-03-12 2004-11-25 Rudolph Michael Lee Photosensitive element for use as flexographic printing plate
US7736836B2 (en) * 2004-09-22 2010-06-15 Jonghan Choi Slip film compositions containing layered silicates
CN101272904B (zh) * 2005-09-26 2012-12-19 尤尼吉可株式会社 阻气性层叠体及层叠物
JP2009139598A (ja) * 2007-12-05 2009-06-25 Toray Ind Inc 感光性樹脂印刷版原版
US8985020B2 (en) * 2011-11-02 2015-03-24 E I Du Pont De Nemours And Company Method and apparatus for thermal treatment of printing surface in relief printing
CN103881034B (zh) * 2012-12-21 2016-03-09 乐凯华光印刷科技有限公司 一种激光热塑性纳微米颗粒及其合成方法与用其制作的平印版
EP3008519B1 (fr) * 2013-06-14 2017-08-09 Flint Group Germany GmbH Elément pour la flexographie numérique avec une couche barrière polaire et ultramince
WO2015063776A1 (fr) * 2013-11-03 2015-05-07 Digiflex Ltd. Film pelable pour précurseur de plaque d'impression flexographique et procédé de préparation de plaque d'impression flexographique

Patent Citations (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0332070A2 (fr) 1988-03-10 1989-09-13 BASF Aktiengesellschaft Procédé pour le développement des plaques d'impression flexographiques exposées selon l'image
US5262275A (en) 1992-08-07 1993-11-16 E. I. Du Pont De Nemours And Company Flexographic printing element having an IR ablatable layer and process for making a flexographic printing plate
EP1069475A1 (fr) 1999-07-13 2001-01-17 BASF Drucksysteme GmbH Elément pour l'impression flexographique présentant une couche détachable par infrarouge et hautement sensible
EP1156368A2 (fr) 2000-05-17 2001-11-21 Tokyo Ohka Kogyo Co., Ltd. Matériau photosensible multicouche pour plaque d'impression flexographique
US20040038147A1 (en) * 2002-08-20 2004-02-26 Ray Kevin B. Flexographic element having an integral thermally bleachable mask layer
WO2005101130A1 (fr) 2004-04-10 2005-10-27 Eastman Kodak Company Procede de fabrication d'un hologramme
US8114566B2 (en) 2006-04-07 2012-02-14 Asahi Kasei Chemicals Corporation Photosensitive resin composition for flexographic printing
US8241835B2 (en) 2008-01-30 2012-08-14 E I Du Pont De Nemours And Company Device and method for preparing relief printing form
EP2284612A1 (fr) 2008-05-23 2011-02-16 Toyo Boseki Kabushiki Kaisha Cliché matrice pour impression flexographique
EP2128702A1 (fr) 2008-05-27 2009-12-02 Esko-Graphics Imaging GmbH Durcissement de plaques d'impressions photo-durcissables permettant d'obtenir des sommets plats ou arrondis
US20120164584A1 (en) 2009-10-01 2012-06-28 Recchia David A Method of Improving Print Performance in Flexographic Printing Plates
CN102103322A (zh) * 2009-12-17 2011-06-22 乐凯集团第二胶片厂 一种计算机直接制版的柔性版及其制备方法
EP2596404A1 (fr) 2010-07-19 2013-05-29 Flint Group Germany GmbH Procédé comprenant une irradiation à del uv pour fabriquer des moules de flexographie
US20120115083A1 (en) * 2010-11-04 2012-05-10 Vest Ryan W Biodegradable Film for Flexographic Printing Plate Manufacture and Method of Using the Same
US8492074B2 (en) 2011-01-05 2013-07-23 Laurie A. Bryant Method of improving print performance in flexographic printing plates
WO2012145111A1 (fr) 2011-04-21 2012-10-26 Macdermid Printing Solutions, Llc Stratifié de résine photosensible et son traitement thermique
US8808968B2 (en) 2012-08-22 2014-08-19 Jonghan Choi Method of improving surface cure in digital flexographic printing plates
WO2015040094A2 (fr) 2013-09-18 2015-03-26 Flint Group Germany Gmbh Élément flexographique pour imageage direct et procédé de fabrication de clichés

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10843453B2 (en) 2016-10-10 2020-11-24 Akk Gmbh Composite panel with barrier layer and method for manufacturing a letterpress plate
JP2018091953A (ja) * 2016-12-01 2018-06-14 旭化成株式会社 フレキソ印刷原版
JP7036536B2 (ja) 2016-12-01 2022-03-15 旭化成株式会社 フレキソ印刷原版
WO2019072701A1 (fr) * 2017-10-10 2019-04-18 Flint Group Germany Gmbh Précurseur en relief avec faible courbure transversale et plissage
US11822246B2 (en) 2017-10-10 2023-11-21 Flint Group Germany Gmbh Relief precursor having low cupping and fluting
JP2021514482A (ja) * 2018-02-16 2021-06-10 ミラクロン コーポレーションＭｉｒａｃｌｏｎ Ｃｏｒｐｏｒａｔｉｏｎ マスク要素前駆体およびレリーフ像形成システム
JP7319282B2 (ja) 2018-02-16 2023-08-01 ミラクロン コーポレーション マスク要素前駆体およびレリーフ像形成システム
EP3832389A1 (fr) 2019-12-06 2021-06-09 Folex AG Plaques d'impression flexographique à haute résolution et moyen de fabrication desdites plaques comprenant des couches barrière et d'adhésion améliorées

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US20180170088A1 (en) 2018-06-21
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EP3633454A1 (fr) 2020-04-08
US10518571B2 (en) 2019-12-31
CN107969149A (zh) 2018-04-27
JP2018517179A (ja) 2018-06-28
ES2781325T3 (es) 2020-09-01
BR112017025209B1 (pt) 2022-04-19
JP7242771B2 (ja) 2023-03-20
EP3304203B1 (fr) 2020-01-01
MX2017015163A (es) 2018-03-28
JP2021167970A (ja) 2021-10-21

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